The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 08, 2015
Filed:
Oct. 15, 2010
Hiroki Nagai, Nagoya, JP;
Masahiro Morita, Toyota, JP;
Takashi Iwao, Kodoma, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota-shi, Aichi, JP;
Abstract
A secondary batteryincludes a positive electrode current collectorand a positive electrode mixture layerwhich is coated over the positive electrode current collector. The positive electrode mixture layerincludes a positive electrode active material, an electrically conductive material, and a binder. In addition, the positive electrode active materialhas secondary particlesformed by an aggregation of a plurality of primary particles of a lithium transition metal oxide, a hollow portionformed in the secondary particle, and through holespenetrating the secondary particlesso as to connect the hollow portionand the outside. A ratio (Vbc/Va) of an inner volume Vbc of holes formed inside the positive electrode mixture layerto an apparent volume Va of the positive electrode mixture layersatisfies 0.25≦(Vbc/Va). In addition, in a section of the positive electrode mixture layer, a ratio (Vb/Vc) of an inner volume Vb of holes B formed inside the positive electrode active materialto an inner volume Vc of holes C formed outside the positive electrode active materialsatisfies 0.05≦(Vb/Vc)≦2.5.